The invention concerns a contacting device for a ribbon cable with a housing top enclosing a number of contacting elements and with a housing bottom, between which the ribbon cable can be passed, a gasket being provided that seals the housing top against the ribbon cable when it is installed.
Ribbon cables are used in a number of areas, for example, in building technology, in the automotive sector or in industrial control and automation technology. They are used both for electrical power supply in the low voltage range, for example, for an electrical system in a vehicle, and also in the ordinary voltage range of a few 100 V for building installation. The ribbon cables have several electrical conductors arranged next to each other, some of which can be used for power supply and some as communications lines.
It is often desirable, especially in building technology and in industrial control and automation technology, to arrange electrical equipment in a spatially flexible manner and to connect it without laying costly installation lines. A ribbon cable laid through the room is particularly suited for this purpose, via which power and communication supply for the connected equipment can occur. The equipment can be connected to the ribbon cable at any location in the room via contacting devices. Both power supply and communication of equipment with each other or with a central office is therefore achieved via ribbon cables. A bus system (field bus) is preferably provided for this. The bus system can be designed as a power bus and/or data bus. In this case the contacting device is designed as a bus adapter, via which the equipment can be connected to the bus system. This type of electrical installation system designed as a bus system is known from EP 0 665 608 A2.
The contacting device is primarily prescribed for those applications in which the conductors of an ordinary ground cable are to be contacted with those of a ribbon cable. A known technique for contacting is so-called penetration contacting in which the contact pins penetrate the covering of the ribbon cable and the insulation of the conductors being contacted. For reliable and permanent contacting, the contact region must be protected from penetration of dirt and water. Different degrees of protection are established by European Standard EN 60 529. The degree of protection IP67 is sought for contacting equipment.
A contacting device of the type just mentioned is known from DE 196 18 998 C1. To achieve a high degree of protection, a sealing element is provided between the ribbon cable and the housing top. This consists essentially of connected O rings. The contact pins or contacting elements are passed through the openings of the O rings and penetrate into the ribbon cable. The sealing element additionally has an elevation on its outer edge in the form of a spring that engages in a correspondingly shaped groove in the housing top. Sealing is obtained via the O rings between the ribbon cable and sealing element and sealing between the sealing element and the housing top is obtained via the groove-spring configuration. A shortcoming in this variant is the complex configuration of the sealing element and the fact that fitting into the groove of the housing top must occur.
The underlying task of the present invention is to offer a contacting device with a simply configured sealing system that guarantees a high degree of protection.
According to it a sealing ridge is provided on the housing top that cooperates with the gasket. Sealing between the gasket and housing top then occurs so that the gasket is pressed against the sealing ridge during assembly. Because of this, reliable sealing is achieved. At the same time the need for a demanding groove-spring configuration drops out, since the gasket need not have a groove in the region of the sealing ridge.
The sealing ridge in a preferred variant is molded directly onto the housing top. It is therefore an integral component of the housing top, which is designed in particular as an injection molded part. This facilitates manufacture.
To achieve the highest possible tightness, the sealing ridge in an advantageous embodiment is arranged continuously around a contacting region in which the contacting elements are situated.
Preferably the sealing ridge tapers to a point in the direction toward the gasket so that the sealing ridge in the installed state presses into the gasket and high sealing is achieved. For example, the sealing ridge is designed to be triangular when viewed in cross section for this purpose. For a simple configuration of the gasket, it is preferably designed to be flat. The gasket is therefore a flat seal and, for example, a rubber strip.
The gasket is preferably designed essentially to be continuous, i.e., has no recesses especially in the region of the contacting elements. This applies at least for the uninstalled state. This has the advantage of extremely simple configuration of the gasket.
The continuous gasket also favors reliable sealing between the gasket and ribbon cable when the contacting element is traversed by the gasket during assembly. The contacting element then displaces the sealing material, which is closely conformed around the contacting element, on the one hand, and forms a small bulge toward the ribbon cable on the bottom of the gasket, on the other hand, which almost has the effect of an O ring. In preferred variants, the contacting elements are guided through the gasket in the installed state, which lie tight against the contacting elements. The contacting elements are then preferably guided through the gasket, the sealing material displaced by the contacting elements forming a continuous bulge around the corresponding contacting element which serves for sealing of the ribbon cable to the corresponding contacting elements. This sealing can be achieved regardless of the sealing obtained via the sealing ridge.
The contacting elements preferably have screws for screwing into the ribbon cables. Contact with the conductors of the ribbon cable is therefore produced via the screws. In contrast to simply designed contacting pins, the screws have the advantage that greater forces can be exerted with them. They are particularly suited for relatively strongly designed ribbon cables. In addition, the penetration depth into the ribbon cable can be adjusted with the screws.
For rapid and simple assembly, the housing bottom preferably has a guide rail into which the housing top can be inserted by means of a guide element. The guide rail is designed for this purpose as a simple profile rail, for example.
The guide rail and guide element then preferably cooperate in the fashion of a hinge. A clearance is set for this purpose preferably between the guide rail and guide element so that swiveling of the two housing parts around a pivot axis formed by the guide rail and guide element is possible. This permits simple assembly of the ribbon cable, since this is inserted into the two swiveled out housing parts, which are then swung back. The two housing parts are appropriately joined, for example, screwed, on the side opposite the guide rail.
In a preferred variant, the housing top is part of a plug-in connector, especially part of the rectangular plug-in connector. The housing top has contact bushings for this purpose to receive contact pins. These are mounted on a plug housing, which is placed on the housing top. It is particularly advantageous if the housing top and plug housing also have means of sealing in order to also achieve degree of protection IP67 for the plug-in connectors.
Such plug-in connectors are known as so-called heavy rectangular plug-in connectors, especially in the field of industrial control and automation technology.
To permit use of the contacting device in a field bus system, for example, in a power bus and/or data bus system, the contacting device is preferably designed as a field bus adapter. Bus subscribers can be connected to the ribbon cable forming the bus lines of the field bus via the adapters.
In an expedient embodiment, the device comprises a control unit, via which the equipment coupled to the field bus can be controlled. For this purpose the control unit has a display and operating element. This has the significant advantage that functions ordinarily arranged in central switch cabinets are arranged decentralized directly in the area of the electrical machine. This increases the user friendliness and simplifies the search for errors, since intricately laid out switch cabinets can largely be dispensed with.
In a particularly expedient embodiment, the adapter has an adapter bottom and an adapter top, in which the latter can be mounted on the adapter bottom. The adapter bottom carries the contacting mechanism, i.e., the contact pins, for contacting with the ribbon cable. The adapter top includes the electronics of the adapter, for example, the electronics of the control unit. The adapter top and adapter bottom are connected to each other in the fashion of a plug-in connector. This has the decisive advantage that the adapter top carrying the electronics can be simply mounted and also simply replaced. This permits the adapter to be easily adapted to different requirements, in which case the adapter top is replaced. The adapter top is preferably also simply replaced for elimination of defects.
A plug connection is preferably integrated in the housing top. The plug connection is configured here, for example, as a connection for a communications line to a communications device or as a connection to a power supply for an electrical load. The plug connection is preferably designed as a connection for a circuit board plug-in connector. Integration of a plug connection in the housing top has the advantage relative to plug-in connectors that the plug connection is arranged internally in the housing top so that means of sealing, as required in a plug-in connector, are not necessary.